Portable buildings or cabanas which are typically used for portable chemical toilets are usually provided with vent or window openings in their wall panels or door panels. Such vent openings are typically formed by cutting a suitable size opening within the panel, framing the opening and covering it with a screen material. Examples of this type of construction are shown in my prior U.S. Pat. No. 3,447,167 issued June 3, 1969 which illustrates such vent openings formed near the bottoms of the cabana panels and the door panel. Another example is my U.S. Pat. No. 4,446,585 issued May 8, 1984 and illustrating vent openings formed near the upper portions of the cabana wall panels. Another similar example of such a vent is shown in U.S. Pat. No. 4,065,885 issued Jan. 3, 1978.
Such conventional vent openings are relatively expensive and somewhat difficult to maintain as they can be easily damaged. Also, then can corrode if the framing is made of metal. Further, they are relatively difficult to repair in the event of damage. Moreover, since the portable building or cabana structures are typically formed of thin wall plastic panels, it is difficult to install a framed vent opening or window which will not become loose or broken free of the plastic panel over a long period of use.
Consequently, the invention herein relates to vent openings that are similar to screened window openings, formed integrally in the plastic sheet panels of portable buildings which are especially useful for portable chemical toilets.